The present invention relates to an outsert molded product formed integrally by molding a metal substrate and a resin material.
An outsert molding process is for injection-molding a resin material in a predetermined position on a metal substrate, for example, by using a molding die. The metal substrate is subjected to such processing as punching, bending and drawing. For the resin material, one having such characteristic as flexibility, slidability and light weight is employed. For the metal substrate, one having such characteristic as a high mechanical strength and a high heat-radiating property is used. A product obtained by such outsert molding process is integrally formed by the metal and resin material. Therefore, in the outsert molded product, various mechanical functions can be provided in a component. In addition, the outsert molding method provides a high mass-productivity and lower component and assembly costs.
FIGS. 5 and 6 show sectional views of a main part of a conventional outsert molded product.
In FIG. 5, the conventional outsert molded product has a metal substrate 1 and a functional element 2 formed by a resin. The metal substrate 1 is a base of the outsert molded product. The functional element 2 provides a function for attachment to the other component or the like. A resin material plasticized to a flowable state is injected through a gate 3 from a nozzle of a resin molding apparatus (not shown) into a metal die (not shown) covering front and back sides of the metal substrate 1. The resin material is directed through a runner 4 to a predetermined position on the metal substrate 1. An anchor 5 is formed by a resin, and serves for securing the functional element 2 against the metal substrate 1. The metal substrate 1 has a fixing hole 6. The fixing hole 6 serves for fixing the anchor 5 to the metal substrate 1 at a sufficient strength. Although the fixing hole 6 is nearly of a circular shape, it may be formed in various shapes according to the shape of the functional element 2.
The resin material injected through the gate 3 is passed through the runner 4 and the fixing hole 6 of the metal substrate 1, and reaches the functional element 2 and the anchor 5. Then, the resin material integral with the metal substrate 1 is cooled. After that, the resin material in the die is cooled. Finally, the resin material integral with the metal substrate is removed from the die. In such manner, an outsert molded product is produced.
Since importance of preserving the global environment has been recently pointed out, such design is demanded even in the field of industrial products that contributes to saving of resources and energy and reduction of wastes. Thus, it is desired to classify waste materials by types in disposal of products, and reuse the classified waste materials. However, in an outsert molded product, a resin material is, as described above, formed on a metal substrate at a sufficient bonding strength. Therefore, it has been difficult to easily separate a metal portion from a resin portion in disposal of the product. For example, in the case the resin material is such high-molecular compound as polyacetal (represented by polyoxymethylene), because a bonding strength between the resin material and a metal is particularly high, it has been difficult to separate the metal from the resin material. Additionally, in an outsert molded product containing a metal with the fixing hole 6 formed therein, it has been required to separate the metal from a resin by crushing a resin portion about the fixing metal 6 into pieces. Thus, a conventional outsert molded product has required a lot of time and labor for such separation, or has been disposed as an industrial waste without being subjected to such separation. Such conventional molding method has never been preferable in terms of environmental protection.
To cope with such problem, a technique described in Japanese Patent Laid-open Publication No. 8-192440 was suggested. FIG. 6 shows a constitution of another outsert molded product of prior art.
In FIG. 6, a resin material injected through a gate 3 is directed through a runner 4 that is located in either side of the metal substrate 1 to a predetermined position in the metal substrate 1. Flows of the molten resin material of a high temperature lead along both sides of the substrate 1 are joined inside the fixing hole 6 of the metal substrate 1 in the anchor 5, and form a weld line 8. A bonding strength between the flows of resin along the weld line 8 is lower than that in the other portion. Therefore, in disposal of a product, a metal portion can be separated from a resin portion by separating the resin portion in a side of the metal substrate 1.
However, in the conventional constitution described above, the molten resin material in the anchor 5 closer to the gate 3 comes in at a high speed in a molten state of a high temperature. As a result, the flows are bonded at a high strength in the weld line 8 formed inside the fixing hole 6 of the metal substrate 1. Accordingly, it is likely that a product cannot be easily broken along the weld line 8 at the time of disposal. In addition, in order to provide a weld line in a desired position, it is required to optimize such molding condition as temperature control of a fluidized resin material and pressure control for injection of the resin through the gate 3 as well as such die design as a structure of the gate and shape of the runner, which has been very difficult. Besides, such controls and die design have posed significant limitation to the degree of freedom in designing the functional element 2 has been significantly limited.
The invention provides an outsert molded product with a metal portion easily separated from a resin portion at the time of disposal of the product without affecting the degree of freedom in designing a die and a product.
An outsert molded product according to the invention comprises:
a metal substrate having a fixing hole,
an anchor fixed to the fixing hole, and formed by a resin, and
a groove formed in at least a surface of the anchor,
wherein the anchor is disposed continuously in the fixing hole and both sides of the substrate including the fixing hole, and the groove is nearly in the shape of a ring formed in such position that the fixing hole is projected nearly in the vertical direction to the substrate.
A method of producing an outsert molded product according to the invention comprises steps of:
(a) setting a metal substrate having a fixing hole in a die,
(b) supplying a resin to a cavity of the die with the metal substrate set therein,
(c) molding the resin, and
(d) removing the outsert molded product formed integrally with the metal substrate from the die,
wherein the cavity is of such shape that an anchor placed in both sides of the metal substrate including an inner side of the fixing cavity and a groove disposed in a predetermined surface of the anchor can be formed therein, and the groove is nearly in the shape of a ring formed in such position that the fixing hole is projected nearly in the vertical direction to the substrate.
A separating method of an outsert molded product according to the invention comprises steps of:
(a) providing an outsert molded product described above,
(b) applying a force from a surface of an inner circumferential part of the groove toward the fixing hole so that the inner circumferential part of the groove including a resin-filled portion that is located in the fixing hole is separated from the outsert molded product, and
(c) separating a resin portion remaining from the metal substrate.
According to such constitution, a substrate portion and a resin portion can be easily separated from each other at the time of disposal of a product. As a result, a significant effect of promoting preservation of the global environment can be obtained.